The Investigation of the Effect of Radiotherapy Intensity onSwallowing and Chewing Structures in Head and Neck Cancer Patients Treated with Concomitant Chemoradiotherapy

Intensity-modulated radiotherapy (chemo-IMRT) and concommitant chemotherapy is a treatment protocol used in many centers for the treatment of head and neck cancers (HNC). Anatomical structures associated with chewing and swallowing may be impaired in early and late periods after radiotherapy. The main purpose of this study is to investigate the relationship between the RT dose and the change in chewing, swallowing functions and quality of life. The study included 35 participants who were treated with chemo-IMRT, with a mean age of 54.31 and 7 female and 28 male. Videofluoroscopic swallowing assessments were performed before chemo-IMRT, 3 and 6 months after chemo-IMRT. These evaluation findings () were scored according to the Modified Barium Swallow Impairment Profile and penetration-aspiration levels were determined via Penetration-Aspiration Scale (PAS). maximum interincisor mouth opening, Functional oral intake scale (FOIS) levels and body mass indices (BMI) of all cases were determined. There was a significant increase in PAS and MBSImp scores; significant decrease in BMI scores of the patients after treatment. In the quality of life findings, xerotomy and sticky saliva complaints increased after treatment. Dose to mastication muscles (>40 Gy), and TMJ (>58 Gy) was found to be associated with the decrease of BMI; dose to SPC muscle (> 58 Gy), was found to be associated with pharyngeal stripping wave. Presence of aspiration was found to be associated with IPC (> 67), GL (> 62), SGL (> 63 Gy) and UES muscles (> 61 Gy). Intensity modulated radiotherapy should be planned to minimize these side effects.